It is sometimes useful to be able to communicate electrical signals, power, etc., between a rotating section and a nonrotating section of a well tool, or between two rotating sections, or between two well tools, etc. For example, in drilling operations, sensors and/or actuators may be located below or in a drilling motor, and it may be desired to communicate sensor measurements to a nonrotating measurement-while-drilling (MWD) tool for telemetering to the surface, or it may be desired to transmit commands and/or electrical power to an actuator across the drilling motor (e.g., to adjust a steering tool).
Therefore, it will be appreciated that improvements are continually needed in the art of communicating electrical signals, power, etc., between sections of a well tools which rotate relative to one another.